Timer mechanism having cam-solenoid actuator and common coil for solenoid and motor



I 1 3 m 0W M 2 m w D 3 m A m M S M 2 U T C A D I 0 m Ev 4 M m R m DI m H Sept. 13, 1966 TIMER MECHANISM COMMON COIL FOR SOLENOID AND MOTOR Filed Sept 24 1963 FIG.4.

INVENTOR. Roger D. Rulseh FIG.2.

TTORNEY Sept. 13, 1966 R- D. RULSEH 3,272,931

TIMER MECHANISM HAVING CAM-SOLENOID ACTUATOR AND COMMON COIL FOR SOLENOID AND MOTOR Filed Sept. 24, 1963 2 Sheets-Sheet 2 INVENTOR Roger D. Rulseh ATTORNEY United States Patent Filed Sept. 24, 1963, Ser. No. 311,064 6 Claims. (Cl. 200-35) This invention concerns interval timers, and more particularly to electrical interval timers which actuate a switch at the end of a preset time interval, and in which the interval measuring mechanism is automatically reset when the timer is turned oif.

Such timers usually contain a clock mechanism, some sort of interval measuring or interval timing mechanism driven by the clock mechanism, and an actuating mechanism for actuating a switch or an alarm at the end of the interval. The clock mechanism requires a synchronous electric timing motor, and separate electromagnetic motors of the type comprising a solenoid and an armature are used to supply the mechanical power to engage the interval timing mechanism with the clock mechanism at the start of the cycle and to operate the actuating mechanism at the end of the cycle. Such a timer may therefore require three bulky motors, which are difficult to fit within a compact timer package.

It is therefore an object of this invention to provide a timer of the type described which, while retaining the advantages of mechanically driven actuating mechanism, and of a clutch for engaging the interval timing mechanism with the clock mechanism, requires fewer motors and may therefore be assembled into a more compact package.

It is another object of this invention to provide a timer of the type described in which the clutch and actuator mechanisms are so interrelated that both may be operated by the same electromagnetic motor.

It is a further object of this invention to provide a timer of the type described in which the solenoid used in combination with an armature to provide mechanical power for the clutch or actuating mechanisms also serves as the field coil for the synchronous timing motor.

It is still a further object of this invention to provide a timer of the type described with an improved clutch mechanism for connecting the interval timing mechanism to the clock mechanism.

For an understanding of the manner in which this invention realizes the above and other objectives, reference should be had to the following detailed description, taken in conjunction with the drawings, which form a part of the specification, and in which:

FIG. 1 is a rear perspective view of the timer with the rear wall removed;

FIG. 2 is a perspective view showing the interconnection of the solenoid and the motor pole pieces, and their position with respect to the timer walls;

FIG. 3 is a fragmentary rear elevational view showing the manner of connection of some of the timer components to the rear wall thereof;

FIG. 4 is a view largely in section of the solenoid and the armature mounted within it;

FIG. 5 is a sectional view taken along line 55 of FIG. 1, but with the rear wall in place and the gears adjacent to the interval timing mechanism shown in full;

FIGS. 6 and 7 are perspective views illustrating the operation of the solenoid in engaging the clutch and operating the switch actuator, with FIG. 6 showing the clutch in engaged position and FIG. 7 showing the switch actuator in switch actuating position; and

FIG. 8 is an elevational view showing the gear train, with portions of some of the gears being cut away for greater clarity.

Turning now to the drawings, specifically to FIG. 1, the components of the illustrated embodiment of the invention are mounted upon, and largely located within, a frame comprising rectangular front and rear walls 10 and 11, respectively, that are held in spaced, parallel relationship by means of cylindrical spacers 12, 13 and 14 and a rigid rectangular terminal strip of insulating material 15, all of which may be attached to walls 10 and 11 by any conventional means not shown. Rear wall 11 has been removed in FIG. 1 so that the component parts are visible (it is shown in section in FIG. 4), and strip 15 is cut in half longitudinally to show the connections to the electrical contact tabs.

The timer may be considered to be composed of a group of principal components and assemblies, which will be identified here briefly before a detailed description is undertaken. The clock mechanism for the timer comprises a rotary synchronous electric motor and a gear train driven by the motor. The stator and rotor assembly 16 of the timing motor occupies the upper right-hand portion of FIG. 1, and gear train 17 is adjacent to it. The interval timing mechanism includes a timing cam 20, a clutch disc 21 (both located at the upper left of FIG. 1), and a presettable stop means for adjusting the timing interval. The stop means is hidden behind timing cam 20 on FIG. 1, but may be seen on FIG. 5 to comprise principally an interval setting gear 22 and a stop member 23. A solenoid 24, located at the lower center of FIG. 1, acts as the field coil for the synchronous timing motor, and in conjunction wtih its axially positioned armature 25, supplies the mechanical power to actuate spring leaf switch 26 and to connect the interval timing mechanism to gear train 17. Solenoid armature 25 drives a slide bar 27 which carries a vertically extending arm 28 for engaging timing cam 20 and a horizontally projecting stud 29 for actuating switch 26.

The construction and interconnection of stator and rotor assembly 16 and solenoid 24, which together comprise the synchronous electric timing motor, may be followed by reference to FIGS. 1 through 4. Stator and rotor assembly 16 is of a generally cylindrical configuration, mounted between, and having a longitudinal axis perpendicular to, walls 10 and 11. It comprises two fixed pole pieces 32 and 33 of magnetic material and a cupshaped rotor 34 mounted for rotary motion within them. Pole piece 32 has a fiat, annular base portion 35 from whose circular periphery equally spaced pole fingers 36 project axially. Base 35 is placed flat against the inner surface of rear wall 11. A cylindrical core 37 of magnetic material fits through a circular opening 38 is annular base 35 and through a corresponding opening (not shown) in abutting rear wall 11. Core 37 projects inwardly from base 35, having its inner end located within the cup-shaped opening of rotor 34, and projects outwardly slightly beyond the outer surface of rear wall 11. Base 35 and core 37 are rigidly mounted upon rear wall 11 by a conventional fastening means (not shown).

Pole piece 33 comprises a flat, annular base portion 40 from whose circular periphery pole fingers 41 project axially. The plurality of pole fingers 41 are equal in number to the plurality of opposed pole fingers 36, and, like pole fingers 36, form an equally spaced annular series. Each pole finger 41 projects slightly into the space between adjacent pole fingers 36 of pole piece 32, and is spaced substantially an equal angular distance from the two pole fingers 36 between which it projects. Pole pieces 32 and 33 and rotor 34 are coaxial.

Flat base portion 40 is fastened, by any conventional fastening means (not shown), to the radial end face of an outwardly extending radial flange 42 which is at one end of hollow cylindrical housing 43, which is fabricated of magnetic material. A short cylindrical portion of reduced diameter 44 extends from the other end of housing 43 and fits loosely within circular opening 45 in front wall and opening 46 in the enlarged end 47 of a bracket 48 of flat magnetic stock, which abuts the outer surface of front wall 10. The axial dimension of reduced diameter portion 44 is equal to the sum of the thicknesses of front wall 10 and bracket 48. Thus, with the inner surface of front wall 10 abutting the shoulder 49 formed by the radial surface connecting the two cylindrical portions of differing diameters, and with flat bracket 48 abutting front wall 10, the outer surface of bracket 48 is flush with the outer transverse surface 50 of portion 44. Reduced diameter portion 44 is generally solid, and contains an axially located threaded recess opening outwardly and adapted to receive a bolt 52. When bolt 52 is passed through a washer 53 having a diameter larger than the diameter of portion 44 and is screwed tightly into the threaded recess in portion 44, its head engages washer 52 and front wall 10 and end 47 of bracket 48 are tightly clamped between washer 53 and shoulder 49, thus mounting the end of bracket 48, pole piece 33, and housing 43 to front Wall 10. This mounting arrangement is advantageous in that, by simply loosening bolt 52 slightly, pole piece 33 may be angularly adjusted to provide any desired angular spacing between pole fingers 41 and oppositely disposed pole fingers 36 of pole piece 32.

Solenoid 24, as may be seen in FIG. 4, includes a spool 53 comprising a hollow cylindrical main portion 54 terminating at its ends in outwardly extending radial flanges 55 and 56. A winding 57 is wound upon spool 53 and occupies the annular channel formed by main portion 54 and flanges 55 and 56. Main portion 54 defines a smooth cylindrical bore 58 extending from the end of portion 54 adjacent flange 55 through most of the axial dimension of portion 54. Cylindrical, solid armature 25 fits slidably within bore 58. A coaxial bore extension 60 extends from the end of bore 58 through the end of main portion 54 adjacent flange 56. A cylindrical plug 61 of magnetic material fits within bore extension 60. An outwardly extending radial flange 62 is fixed to plug 61 near its inner end and. by engaging shoulder 63 formed by the radial surface connecting bore 58 and bore extension 60, prevents plug 61 from being withdrawn axially from bore 60. The other, or outer, end of plug 61 projects substantially beyond the outer surface of radial flange 56.

The projecting end of plug 61 is received within circular opening 66 in arm 67 which is bent inwardly from bracket 48 at a right angle (FIG. 2) and extends through a suitable opening in front wall 10. The transverse outer end surface 68 of plug 61 advantageously projects just slightly beyond the surface of arm 67 and is staked thereto, thus rigidly connecting together arm 67, plug 61 and spool 53.

Another bracket 70, formed of flat magnetic stock, includes two angled arms 71 and 72, both of which lie flat against the outer surface of rear wall 11, with arm 71 extending downwardly at an acute angle from the top edge 69 of rear wall 11 and arm 72 extending downward vertically from the end of arm 71. A flange 73 is bent inwardly from, and makes a right angle with, downwardly extending arm 72, passes through a suitable opening in rear wall 11 and lies flat against the outermost surface of spool flange 55, to which it may be attached by any conventional fastening means not shown. A recess 74, Whose width is slightly greater than the diameter 'of that portion of armature 160 which fits slidably within spool 53, opens into the end of flange 73, permitting solenoid 24 to be fitted within flange 73 by a radial movement. The inner end 75 of recess 74 is of semicircular configuration to conform to armature 160 and permit the armature to slide within it. At the other end of bracket 70 (see FIG. 3), a circular opening 76 in the enlarged end 77 of arm 71 fits slidably over the end of core 37 which projects beyond the outer surface of rear wall 11, with the inner surface of end 77 abutting rear wall 11. The outer surface of core 37 advantageously projects just slightly beyond the outer surface of enlarged end 77 and is staked thereto, thus fixing one end of bracket 70 to core 37 and wall 11.

When solenoid 24 is energized by alternating current energy, the alternating magnetic field generated thereby will be coupled from the end of the solenoid adjacent flange 56 via bracket 48 and hollow housing 43 to pole piece 33. The magnetic path at the junction of bracket 48 and housing 43 may be enhanced by making bolt 52 and washer 53 also of magnetic material, in which case the magnetic field is additionally coupled from bracket 48 to housing 43 via washer 53 and then through bolt 52 which extends in threaded contact with the interior of housing 43. The magnetic field at the other end of solenoid 24, adjacent to flange 55, is coupled to pole piece 32 via bracket 70 and core 37. The magnetic flux path is completed by passage across the air spaces between fingers 36 and 41;

Rotor 34, which may advantageously be molded from a synthetic resinous ferromagnetic composition or a ceramic ferromagnetic material, is permanently magnetized in any pattern which adapts it to be driven by a rotating magnetic field. It may thus be magnetized so as to have a plurality of peripheral areas spaced equally about the rotor and magnetized axially of the rotor. For a detailed description of the operation of motors having similar rotor and pole piece configurations, reference may be had to Patents 2,981,855 to Van Lieshout et a1. and 3,014,141 to Riggs.

Rectangular notches 78 in the ends of each of pole fingers 41 and 36 open in the same angular direction and provide sufficient unbalance of the magnetic field to insure certain starting of the motor. They thusprevent the rotor 34 from stopping on a dead center spot in which all the magnetic forces are equally balanced.

Rotor 34 is fixed mounted upon a shaft 811 which is suitably journaled in housing 43 and carries a motor pinion 81, both shaft and motor pinion being shown in end view in FIG. 8. (Shaft 80 and motor pinion 81 are shown only in FIG. 8.) Motor pinion 81 is located within hollow housing 43 and access to it for connecting it with train 17 is had through slot 82 in housing 43. Reduction gear train 17, which may be viewed in FIGS. 1 and 8, comprises principally a series of gears mounted upon three parallel shafts 84, 85, and 86 which are perpendicular to walls 10 and 11. Shafts 84 and 85 are conveniently journaled in opposed bearing holes in those walls, and shaft 86, which does not extend the full distance between the walls, is journaled at one end only in a suitable bearing 86a placed in an appropriate opening in rear wall 11. Gear 87 is fixed to shaft 84 and engages motor pinion 81 through slot 82. Through pinion 88, also fixed to shaft 84, it drives gear 89 and pinion 90 which are fixed to shaft 85. Pinion 911 in turn drives gear 91 and the final take-off pinion 92 which are fixed to shaft 86.

Details of the interval timing'mechanism may be seen most clearly in the sectional view of FIG. 5 and in the enlarged perspective view of FIGS. 6 and 7. Both timing cam 20 and clutch disc 21 are rigidly mounted upon timing hub 95. Hub 95 comprises two integral cylindrical portions of approximately the same axial length and having different diameters. The portion of larger diameter 96 is closer to front wall 111 and is provided at its end with an outwardly extending radial flange 98; the cylindrical portion of smaller diameter 97 extends rearwardly toward rear wall 11. Timing cam 20 has an axially located circular opening 99 which is adapted to receive cylindrical portion 97. Timing cam 20 is fixed upon cylindrical portion 97 abutting shoulder which is formed by the radial surface of hub 95 which connects the portions 96 and 97 of differing diameter.

Clutch disc 21 comprises an annular central portion 102 whose inner diameter receives, and which is fixed to, cylindrical portion 97 of hub 95. It is connected by a radial web 103 with an axially projecting annular rim 104. An annular groover 105 in the periphery of rim 104 is adapted to receive an O-ring 106 of rubber or similar resilent material. Disc 21 is placed upon cylindrical portion 97 of hub 95 with its end surface abutting the surface of timing disc 20. Both timing disc and clutch disc 21 are fastened to hub by any conventional means not shown.

Hub 95 has an axial bore 107 adapted to slidably receive shaft 108. One end 109 of shaft 108 is journaled in slot 110 in rear wall 11. Slot 110, as may be seen in FIG. 5, has a horizontal dimension substantially larger than the diameter of shaft 108, permitting horizontal movement of that shaft in the slot; slot 110 has a vertical dimensions which is just slightly larger than the diameter of shaft 108 and thus permits sliding movement of that shaft therein. A portion 111 of shaft 108 near end 109 is knurled and a cylindrical spacing sleeve 112 is forced over shaft 108 with its knurled portion 111 creating a tight rigid fit between the shaft and the sleeve. The outer diameter of sleeve 112 is larger than the vertical dimension of slot 110; sleeve 112 therefore spaces hub 95, which is slidably mounted upon shaft 108, from rear wall 11. A coil spring 113 has one end 114 curved around to fit within an annular grove 115 in spacing sleeve 112. The other end 116 of spring 113 is curved around and engages a projection 117 from rear wall 11. Coil spring 113, which is in extended position, therefore serves to bias the rear end 109 of shaft 108 away from the take-off pinion 92 of gear train 17. The other end of hub 95 is axially retained on shaft 108 by means of a washer 118 which may advantageously be of the type snapped into position in an annular groove on the shaft.

The other end 120 of shaft 108 is loosely journaled in a bearing bore 121 opening into one end of, and extending axially of, setting gear hub 122. On its inner end, bearing bore 121 opens into a smooth cylindrical bore 123 which is coaxial with it and extends through the hub, opening into its other end. The exterior of hub 122 comprises a series of short cylindrical sections progressively decreasing in diameter as they approach front wall 10. Circular, externally toothed interval setting gear 22 is rigidly mounted upon one of these portions of decreasing radius 124, being butted up against the shoulder 125 formed by the radial surface connecting section 124 with portion 126 of maximum diameter. The sleeve portion 128 of a flanged bushing 129 is received within bore 123 and is rigidly fastened to the bore wall by a conventional fastening means not shown so that hub 122 and flanged bushing 129 are rigidly fixed together. Sleeve portion 128 has a smooth cylindrical bore 130, and the portion 131 of shaft 108 passing through bore is of reduced diameter to provide clearance between the shaft and the bore wall.

Sleeve 128 connects with an outwardly extending radial flange 13 2. The portion of sleeve 128 adjacent to flange 132 is journaled in a sleeve bearing 133 which is mounted within a suitable opening in front wall 10 and protrudes slightly on either side of this wall. Similar thin flat washers 134 and 135, of fiber or some similar material adapted to provide a high coefficient of friction with an abutting surface, are placed around sleeve bearing 133 adjacent to the outside and the inside of front wall 10, respectively, with their exposed surfaces being flush with the ends of bearing 133. A spring washer 137 has an annular concavity facing the outer surface of washer 134, has its periphery bearing upon the outer surface of 134 and has the portion adjacent its circular opening placed between the outer surface of sleeve bearing 133 and the inner radial surface 138 of hub 122. The spring action of washer 137 is such that the portion sandwiched between sleeve bearing 133 and the inner surface 138 of hub 122 tends to force hub 122 outwardly, keeping the surface of radial flange 132 pressed tightly up against the exposed surface of washer 135.

A short annular extension 139, coaxial with and of greater outside diameter than sleeve 128 projects inwardly from the inner surface of radial flange .132. A thin flat disc 140, comprising a portion of stop member assembly 23, has an axial opening which is mounted upon and rigidly attached, via conventional means not shown, to the outer surface of annular extension 139. A radial projection 141 from disc bears a circular opening 143 and an inwardly projecting stud 142 mounted Within it. Stud 142 is fixed to projection 141 by conventional fastening means not shown. Both disc 1'40 and projection 141 may be seen more clearly in FIG. 6. An O-ring 144 of rubber or similar resilient material is mounted within an annular recess 145 located near the inner end of projecting stud 1'42. Setting gear 22; hub 122; bushing .129; and stop member 23, comprising disc 140 with extension 141, stud 142, and O-ring 144; are all connected to form a rigid assembly. Because of the action of spring washer 137 in forcing flange 132 against fiber washer 135, While this assembly may be rotated about its axis, it fits quite tightly upon front wall 10 because of the high coeflicient of friction existing between the outer surface of flange 132 and the abutting inner surface of fiber washer 135.

Stop member 23 and timing-cam 20 are mechanically connected by means of a coil spring 147 which is placed about cylindrical portion of larger diameter 96 of hub 95 and is maintained in place axially at one end by timing cam 20 and at the other end by radial flange 98. One end 148 of spring 147 is bent to extend axially and protrudes through a hole in timing cam 20, thus fastening that end of the spring to the timing cam. The other end 149 of spring 147 is attached to stop member 23 by being bent around stud 142.

As may be seen most clearly from FIG. 6, timing cam 20, while substantially a flat disc, has a peripheral opening defined by two radial edges 151 and 152. A flange 153 extends axially from radial edge 151 toward stop member 23, with the axial dimension of the flange being suflicient so that the flange will contact O-ring 144 on stop member 23, as may be seen in FIG. 6. Spring 147 biases timing cam 20 counterclockwise with respect to stop member 23 as viewed in FIG. 6, so that normally timing cam 20 will be positioned with that surface of flange 153 which faces away from the opening abutting O- ring 144.

Turning now to FIGS. 1 and 4 for a description of slide bar 27 and its connection to the frame and to solenoid 24, it will be seen that the slide bar is constructed of flat stock and has an elongated, generally horizontal portion 154 which is placed flat against the inner surface of front wall 10. Two horizontal slots in portion 154 receive spacers 13 and 14 and permit horizontal motion of slide :bar 27. The slide bar is retained against the inner surface of front Wall 10 by radial flanges 15 5 and 156 flxed to spacers 13 and 14, respectively. Flanges 155 and 156 are positioned :far enough from the inner surface of front wall 10 to permit slide bar 27 to slide freely in a horizontal direction. The slot in elongated portion 154 which cooperates with spacer 1-3 is hidden beneath flange 155. The slot 157 at the other end of portion 154, which cooperates with spacer 14 is visible and opens into the end of portion 154.

As may be seen fro-m the partial section of FIG. 4, armature 25 comprises a main portion 160 which is solid and of cylindrical shape and one end of which is received within solenoid bore 58. An outwardly extending radial flange 161 on the projecting end of main portion 160 limits the travel of armature 25 inwardly into bore 58 of solenoid 24 by contacting the surface of bracket 23. A cylindrical armature extension 1162 is coaxial with and of substantially smaller diameter than main portion 160 and projects outwardly from the end of main portion 160 away (from the solenoid proper. A flange 15 9 is turned inwardly at right angles to elongated portion 154 of slide bar'27 and provides the connection of slide bar 27 to armature and solenoid 24. Armature extension 162 makes a sliding fit within a circular opening 163 near the end of inwardly turned flange 159. C-oil spring 164, mounted upon cylindrical extension .162, biases flange 159 against the shoulder formed by the radial sunfa'ce connecting extension 162 with the main armature portion 160 of greater diameter. Coil spring 164 at one end abuts washer 16 which fits slidably upon armature extension 162 and at its other end abu-ts washer 166 which is retained upon armature extension 162 by means of a snap ring or the like 167 which may advantageously snap into an annular 'groove (not shown) upon the armature extension.

A coil spring 168 located within bore 58 of solenoid 24 biases armature 25 in a direction tending to push the armature out of the solenoid bore. The innermost end of spring 164 abuts the inner radial surface of flange 62 and is retained in the space between the outer cylindrical surface of the inwardly projecting end of plug 611 and the wall defining bore 5 8. The other end of spring 168 rests against the inner radial surface of the armature main portion 160 and is retained between the wall defining bore 58 and an inwardly extending annular pro-. jection v169 from main portion 160 which is coaxial with and has a somewhat smaller diameter than does the main portion.

The biasing action of coil spring 16% tends to push slide bar 27 to the left as viewed in FIG. 1. The movement of slide bar 27 to the left is limited by the right-hand limit of the .slot which cooperates with spacer 13 and which is hidden under flange 155 connected to that spacer. The limit of movement of slide bar 27 to the right, as viewed in FIG. 1, is controlled by the movement of armature 25 into bore 58 of solenoid 24, which inward movement, as mentioned above, is limited by the abutment of flange 161 against bracket 73.

The ultimate purpose of the movement of slide bar 27 is the actuation of switch 26 by horizontally projecting stud 29. Switch 26 is of conventional construction and comprises three vertically extending, generally parallel spring leaves, left-hand leaf 171, center leaf 172, and right-hand leaf 173, with their names corresponding to their positions as viewed on FIG. 1. Leaves 171, 172 and 173 are connected at their lower ends to terminals 174, 175, and 176, respectively, by any conventional means, such as riveting or soldering. These terminals are connected to terminal strip 15, as by riveting, and project downwardly from the bottom of the terminal strip.

Center leaf 172 is sufficiently shorter than the other two so that stud 29 in its horizontal movement will not contact leaf 172 but will contact facing surfaces of either left-hand leaf 171 or right-hand leaf 173. Center leaf 172 carries a contact on each of its two surfaces, each contact being adapted to make electrical connection with one of the oppositely disposed contacts located on lefthand leaf 171 and right-hand leaf 173. The switch leaves are mounted so that the two outer leaves are biased inwardly toward center leaf 172 by their own inherent resilience. Thus, if stud 29 were removed, both leaves would spring inwardly toward center leaf 172 with the contact on each of the outer leaves making electrical connection with a corresponding contact mounted on center leaf 172. With slide bar 27 at the extreme leftward extent of its permissible travel, as viewed in FIG. 1, stud 29 bends left-hand leaf 171 backward away from center leaf 172 so that it is not making contact therewith, and right-hand leaf 173 will be self-biased into contact with center leaf 172. In the extreme right-hand limit of the travel of slide bar 27, stud 29 bends right-hand leaf 173 back away from and out of engagement with 183 is in engagement with the periphery of ratchet wheel 8 center leaf 172, and left-hand leaf 171 is in contact with the center leaf.

The AC. power for solenoid 24 is received via terminals 177 and 178 which project downwardly from terminal strip 15 and are connected to it in the same manner as terminals 174, and 176. The power is applied to the ends of solenoid winding 57 via wires 179 and 180' which are connected to terminals 177 and 178, respectively. The AC. power applied to terminals 177 and 178 is the primary power used to operate the timer; the external circuit or circuits to be controlled by the timer are connected to terminals 174, 175 and 176.

A synchronous motor of the type described herein is capable, when first started, of rotation in either direction. Therefore, an anti-reverse mechanism is included in gear train 17 to allow rotation of the motor and gear train in only the desired direction. The anti-reverse mechanism used may be seen in FIG. 1 and comprises basically a ratchet wheel 180 acting in cooperation with an antireverse arm 181. Ratchet wheel 180 is fixed to shaft 84 and bears a plurality of ratchet teeth, each tooth having a smooth cam surface of gradually increasing radius moving in the clockwise direction, as viewed in FIG. 1, and ending sharply in an inwardly extending radial surface. Anti-reverse arm 181 is mounted for pivotal motion about shaft 182, which shaft is disposed perpendicularly to walls 111 and 11 and is journaled in suitable bearing holes in those walls. The end of arm 181 adjacent to ratchet wheel 180 bears two curved arms which act in cooperation with the ratchet wheel, an upper curved arm 183 and a lower curved arm 184, with the positional descriptions of these arms corresponding to their relative positions as viewed in FIG. 1. With the timer mounted as shown in FIG. 1, the weight of anti-reverse arm 18 1 pivots it downwardly, as shown, so that upper curved arm As long as shaft 84 is rotating in the desired counterclockwise direction (as viewed in FIG. 1), the end of curved arm 183 will ride along the smooth, ascending cam surfaces of the ratchet teeth, permitting rotation of the shaft. Should, however, the motor start in the wrong direction, driving shaft 84 clockwise, the end of curved arm 183 will immediately engage the radially extending surface of one of the ratchet teeth, blocking any further motion of shaft 84 in the clockwise direction. The synchronous motor, no longer able to rotate in the wrong direction, will commence rotation in the opposite direction. Should the timer be mounted in an attitude inverted from that shown in FIG. 1, the weight of arm 181 would pull lower curved arm 184 into contact with ratchet Wheel 1811, providing an anti-reverse action identical to that just described.

The desired direction of motor rotation is that which will drive clutch disc 21 in a clockwise direction as viewed in the drawings, and reference to FIG. 8 shows that this requires clockwise rotation of pinion 81. This, as may be seen, results in a counterclockwise rotation of gear 87, which was the permitted direction of rotation described above in connection with the description of the anti-reverse mechanism. To drive motor pinion 81 in a clockwise direction as viewed in FIG. 8, motor rotor 34 must turn in a clockwise direction as viewed in FIG. 1.

In order to understand the operation of the timer, it is desirable first to consider the relationship of the parts existing in the deenergized state, prior to the application of AC. p wer to the solenoid. With solenoid coil 57 deenergized, coil spring 16 8 biases armature 25 in such a manner as to push it out of the solenoid bore 58. The limit of this outward travel is established by the right-hand limit or right-hand side of the slot in longitudinal portion 154 of slide bar 27 which is placed immediately beneath radially extending flange 155. With spacer 13 abutting the right-hand end of this slot, slide bar 27 is at its extreme left position. Stud 29, mounted upon slide bar 27, bends spring leaf 171 back, preventing contact between spring leaves 171 and 172 and permitting contact between spring leaves 172 and 173. The tip of upwardly extending arm 28 of slide bar 27, which ends approximately to a horizontal plane passing through the axis of timing cam 20 and clutch disc 21, is spaced to the left slightly away from the periphery of timing cam 20. Coil spring 113 is biasing the assembly of timing cam 20 and clutch disc 21 away from the gear train, and O-ring 106 of the clutch disc is not in contact with the axially serrated surface of take-off pinion 9-2. The synchronous motor is, of course, not operating. This deenergized position of the timer is shown in FIG. 1, and in dotted line in FIGS. and 6.

Prior to energizing the timer, the desired timing interval is preselected by rotating setting gear 22 by any manual or automatic means not shown. By suitable rotation of setting gear 22, stop member 23, which is rigidly connected thereto, may be adjusted to any desired angular position. Since stop member .23 is mounted in rather tight frictional engagement with front wall 10, it maintains its preset angular position, and coil spring 147 causes timing cam 20 to rotate with respect to stop member 23 until flange 1'53 rests against O-ring 14 4. The fact that the stop member assembly 23 is rather tightly mounted upon wall 10, whereas timing cam 20 is loosely mounted for rotation upon shaft 108, results in the timing cam following the angular position of the stop member rather than vice versa. The initial deenergized position of timing cam 20, which is preset by adjustment of stop member 23, determines the extent or length of the timing interval, since, as will be described below, the angular position of timing cam 20 which defines the end of the timing interval is fixed. Cam 20 measures the extent of the time interval by rotation from adjustable initial angular position to a fixed final angular position.

The timer is energized by the application of the appropriate A.C. power (which will ordinarily be standard 60-cycle, 115-volt, single phase A.C.) to winding 57 of solenoid 24 via terminals 177 and 17 8 and wires 179 and 180, respectively. The magnetic field created by energized winding *57 is coupled by brackets 70 and 48 to pole pieces 32 and 3 3, respectively, of stator and rotor assembly 1 6 as described previously. The motor starts to operate, driving gear train 17 so as to rotate take-off pinion 9-2 in the counterclockwise direction as viewed in FIGS. 1 and 8.

The energization of solenoid 24 also retracts armature 25, pulling it int-o bore 5 8 until flange 161 hits bracket 73. Coil spring 164, located on the end of armature 25, urges flange 159 of slide bar 27 against armature flange 16-1, and tends to cause slide bar 27 to move toward the right as viewed in the various figures, following the retracting armature. However, the slide bar cannot follow the armature very far. The tip of vertically extending arm 28 of slide "bar 27 is spaced only a very slight distance from the periphery of timing cam 29, the distance being much less than the distance of armature travel. Slide bar 27 follows retracting armature 25 only a slight distance to the right before the tip of arm 28 comes into contact with timing cam 20.

When arm 28 contacts timing cam 20, coil spring 164 on armature 25 is urging arm 28 to the right, tending to push the timing cam and clutch disc assembly to the right, and coil spring 113, attached to sleeve 112 and to the frame, is opposing the action of spring 164 and tending to retain the timing cam and clutch disc assembly in its left-hand positiOn. The force of spring 164 is sufliciently strong to overcome the opposed force of spring 113, so that slide bar 27 continues to move to the right, with arm 28 pushing the timing cam and clutch disc assembly to the right against the bias of spring 113 until O-ring 106 on clutch disc 21 engages the serrated periphery of 'take oif pinion 92. The distance necessary to move arm 28 to the right far enough to engage the clutch is less than the extent of travel available to armature 25. Once the clutch is engaged, the periphery of timing cam 20 prevents vertical arm 28 from moving any further toward the right. Thus, since flange 159 is slidably mounted on armature extension 162, armature 25 will continue to retract after the clutch disc engages take-off pinion 92, with flange 159 compressing coil spring 164. During this clutch-engaging motion of slide bar 27, stud 29 does not move far enough to the right to permit left-hand spring leaf 121 to contact center spring leaf 172. Therefore, the electrical condition of switch 26 remains the same. The relationship of the timer components immediately after the energization of solenoid .24 at the beginning of a timing cycle is shown in full line in FIGS. 5 and :6. It should be noted in comparing FIGS. 5 and 6 that, for convenience of presentation, stop member 23 is shown occupying a different angular position in FIG. 5 than it does in FIG. 6.

Compressed coil spring 164, acting through vertical arm 28, maintains O-ring 106 of clutch disc 21 in sufficiently tight engagement with take-off pinion 92 that sufficient friction is produced between the longitudinal serrations of the take-off pinion and the relatively resilient material of O-ring 106 to cause clutch disc 21, and timing cam 20 rigidly connected thereto, to be driven in a clockwise direction by gear train 17. Clutch disc 21 and timing cam 20 may be turned by the clock mechanism even though vertical arm 28 is tightly pressed against the timing cam, since the frictional engagement between take-off pinion 92 and O-ring 1116 is much greater than the friction between the two smooth metallic surfaces of vertical arm 28 and the periphery of timing cam 20. Timing cam 20 leaves its initial angular position in which flange 153 rests against O-ring 144, and is rotated in a clockwise direction at a constant rate by the clock mechanism. The end of the timing cycle is reached when timing cam 21) has rotated far enough in a clockwise direction for radial edge 152 to clear the top edge of vertical arm 28. Vertical arm 28 is no longer in contact with the periphery of cam 20 and moves to the right into the opening defined by vertical edges 151 and 152 as slide bar 27 is impelled to the right by the bias of coil spring 164 until flange 159 hits the outer surface of armature flange 161, as shown in FIG. 7. With vertical arm 28 no longer engaging timing cam 20, clutch disc 21 returns, because of the bias of coil spring 113, to its original position, disengaged from take-off pinion 92, so that the timing gear and clutch disc assembly is no longer driven by the clock mechanism.

This right-hand motion of slide bar 27 brings stud 29 out of engagement with left-hand spring leaf 171, allowing it to spring into contact with center spring leaf 172, and into engagement with right-hand spring leaf 173, bending it back out of engagement with center spring leaf 172. It will therefore be seen that an external circuits connected between spring leaves 171 and 172 remains open during the timing interval and closes at the end of the interval; and conversely an external circuit connectedbetween spring leaves 172 and 173 remains closed during the timing interval and is opened at the end of the interval. The timer is versatile in that either type of circuit operation may be provided. The positions of the timer components at the end of the timing cycle, with solenoid 24 still energized, is shown in FIG. 7.

As long as A.C. power remains connected to solenoid 24, the timer will be maintained in the position shown in FIG. 7. An automatic reset feature is provided whereby, when the timer is deenergized, the components are automatically reset so that the timer will repeat the preset timing interval when it is again energized. When the timer is deenergized by turning off the A.C. power to solenoid 24, armature 25 is no longer retracted into bore 58 by the magnetic field of winding 57 and is forced outwardly by coil spring 108. This forces slide bar 27 to its left-hand limit of travel, moving vertical arm 28 to a switch actuator mounted for movement from a first position toward which it is normally biased through an intermediate position to a switch actuating position;

said switch actuator in said intermediate position engaging said timing cam when said cam is in other than said second rotary position and thereby shifting said combination of cam and clutch surface into said engaged position, with said actuator being blocked by said timing cam from movement into said switch actuating position;

means carried by said cam for disengaging said actuator from said cam when said cam reaches said second rotary position, whereby said actuator is unthe left out of the opening in timing cam 20 defined by edges 151 and 152. Timing cam 20 is free to spring back in a counterclockwise direction under the bias of spring 147 until it reaches its initial position with flange 153 resting upon O-ring 144 of stop member 23. All of the timer components are thus in their initial positions and will repeat the identical cycle whenever the timer is reenergized.

While a preferred embodiment of this timer has been described in detail, it is obvious that many variations and modification which may suggest themselves to those skilled in the art may be made without departing from the scope of the invention, which is defined solely in the claims.

What is claimed is:

1. An electrical timer including in combination a clock mechanism including a synchronous electric timing motor, said motor having pole pieces for the transmission of the magnetic field required for operblocked for movement to said switch actuating position, and said cam clutch combination is returned to said disengaged position by said means normally biasing the combination of said timing cam and said clutch surface toward said disengaged position;

ation of said motor; a solenoid;

a timing cam mounted for rotation about its axis from means magnetically coupling said motor pole pieces to a first rotary position toward a second rotary posisaid solenoid to provide the magnetic field for said tion; motor when said solenoid energized with alternating biasing means normally biasing said timing cam tocurrent; and

ward said first rotary position; an armature connected to said switch actuator, said means to permit adjusting one of said rotary positions armature being magnetically coupled to and actuataof said timing cam; ble by said solenoid to bias said actuator toward a clutch surface fixedly connected to said timing cam; said switch actuating position when said solenoid is the combination of said timing cam and said clutch i d,

surface shiftable from a disengaged position to an 3, A tim r comprising th o bi ti of engaged position in which said clutch surface ena l k h i gages said clockmechanism so that said im g C a switch actuator mounted for movementthrough an is driven from said first rotary position t w a intermediate position to a switch actuating position; second rotary position when said timing motor is a h ft; operating; an interval timing cam mounted for rotation about said means normally biasing the Combination f Said liming shaft from a first rotary position toward a second rocam and said clutch surface toward said disengaged w i i position; presettable stop means determining said first rotary a solenoid; position;

means magnetically coupling said motor pole pieces to 40 means normally biasing said timing carn toward said said solenoid to provide the magnetic field for said first rotary position; motor when said solenoid is energized with alternata l t h di fi dl connected to id ing current; 'sai-d shaft being mounted for movement from a first switch actuating means engaging said cam W Said position in which said clutch disc is disengaged from solenoid is energized, and movable to a switch actusaid clock mechanism toward a second position in aiiilg Position when Said timing Cam is in Said which said clutch disc is engaged with said clock 0nd rotary position; mechanism so that said timing cam is driven by said an armature magnetically coupled with and actuatable clock mechanism from said first rotary position toby said solenoid upon energization of said solenoid d id Second rotary position; with alternating current; and means normally biasing said shaft toward said first posimeans operable in response to actuation of said arrnation;

ture to move said combination of t mi g Cam a said switch actuator and said timing cam being so clutch surface to said engaged positio mounted with respect to each other that said actu- 2- An electrical timer including i11 combination ator, when in said intermediate position, engages said a clock mechanism including a synchronous electric h id cam i i oth than aid second timing motor, Said motor having P Pieces for the rotary position, said actuator thereby moving said transmission of the magnetic field requiwd p shaft to said second shaft position and said cam ration 0f Said motor; blocking said actuator from movement to said switch a timing cam mounted for rotation about its axis from actuating iti n, id tuator being released from a first rotary position toward a second'rotary posiengagement ith id cam when said cam reaches iiofl; said second rotary position, whereby said actuator is ng m ns n rmally biasing d timing Cam unblocked for movement into said switch actuating ward said first rotary position; position said shaft is returned to said first shaft posimeans to permit adjusting one of said rotary positions i b id means normally biasing said shaft toof said timing cam; ward said first position; and

a Clutch Surface fiXediY Connected to said timing means to bias said switch actuator toward said switch the combination of said timing cam and said clutch t ti iti Surface shiftable from a disengaged position to an 4. An electrical timer including in combination engaged Position in which Said clutch Surface a first motor supplying mechanical power for operation gages said clock mechanism so that said timing cam of id i is driven from said first rotary position toward said said first motor comprising second rotary position when said timing motor is l id having a opening therein, and opfifaiing; an armature magnetically coupled with said solemeans normally biasing the combination of said timing id d slidably ounted in said opening of cam and said CllltCh surface toward said disengaged aid solenoid for movement from a first p 5 Position; tion to a second position in response to energization of said solenoid with alternating current;

a second motor supplying mechanical power for operation of said timer, said second motor being at a location remote from said solenoid;

said second motor comprising a rotary synchronous electric motor, said rotary synchronous electric motor including a rotor, and pole pieces positioned adjacent said rotor; magnetic circuit means connected between said pole pieces and said solenoid for magnetically coupling said pole pieces to said solenoid;

whereby said solenoid magnetically coupled to said second motor, and when energized with alternating current, the solenoid supplies, via said magnetic circuit means, the magnetic field required for operation of said second motor at a location remote from said solenoid.

5. A timer in accordance with claim 3 and wherein:

said shaft is loosely journaled at one end and is mounted with substantial freedom of motion in one direction at the other end, whereby the movement of said shaft eifected by the engagement of said switch actuator with said timing cam comprises a pivotal movement about the point at which said one end is loosely journaled.

6. An electrical timer in accordance with claim 4 wherein:

a solenoid is cylindrical; and said magnetic circuit means comprises a first connector element of magnetic material,

and a second connector element of magnetic material; said first connector element being connected between one end of said solenoid and one pole piece of said second motor and said second connector element being connected between the other end of said solenoid and another pole piece of said second motor.

References Cited by the Examiner UNITED STATES PATENTS 2,163,419 6/1939 Warren 200 X 2,223,207 11/1940 Ellis 20035 X 2,479,922 8/1949 Gates et a1. 20035 2,541,830 2/1951 Phaneuf 310-164 2,979,580 4/1961 Timm et al 2.0038 2,981,808 4/1961 Klein 200-38 2,984,716 5/1961 Timm et al 200-38 BERNARD A. GILHEANY, Primary Examiner.

R. K. SCHAEFER, Examiner.

H. M. FLECK, Assistant Examiner. 

1. AN ELECTRICAL TIMER INCLUDING IN COMBINATION A CLOCK MECHANISM INCLUDING A SYNCHRONOUS ELECTRIC TIMING MOTOR, SAID MOTOR HAVING POLE PIECES FOR THE TRANSMISSION OF THE MAGNETIC FIELD REQUIRED FOR OPERATION OF SAID MOTOR; A TIMING CAM MOUNTED FOR ROTATION ABOUT ITS AXIS FROM A FIRST ROTARY POSITION TOWARD A SECOND ROTARY POSITION; BIASING MEANS NORMALLY BIASING SAID TIMING CAM TOWARD SAID FIRST ROTARY POSITION; MEANS TO PERMIT ADJUSTING ONE OF SAID ROTARY POSITIONS OF SAID TIMING CAM; A CLUTCH SURFACE FIXEDLY CONNECTED TO SAID TIMING CAM; THE COMBINATION OF SAID TIMING CAM AND SAID CLUTCH SURFACE SHIFTABLE FROM A DISENGAGED POSITION TO AN ENGAGED POSITION IN WHICH SAID CLUTCH SURFACE ENGAGES SAID CLOCK MECHANISM SO THAT SAID TIMING CAM IS DRIVEN FROM SAID FIRS ROTARY POSITION TOWARD SAID SECOND ROTARY POSITION WHEN SAID TIMING MOTOR IS OPERATING; MEANS NORMALLY BIASING THE COMBINATIN OF SAID TIMING CAM AND SAID CLUTCH SURFACE TOWARD SAID DISENGAGED POSITION; A SOLENOID; MEANS MAGNETICALLY COUPLING SAID MOTOR POLE PIECES TO SAID SOLENOID TO PROVIDE THE MAGNETIC FIELD FOR SAID MOTOR WHEN SAID SOLENOID IS ENERGIZED WITH ALTERNATING CURRENT; SWITCH ACTUATING MEANS ENGAGING SAID CAM WHEN SAID SOLENOID IS ENERGIZED, AND MOVABLE TO A SWITCH ACTUATING POSITION WHEN SAID TIMING CAM IS IN SAID SECOND ROTARY POSITION; AN ARMATURE MAGNETICALLY COUPLED WITH AND ACTUATABLE BY SAID SOLENOID UPON ENERGIZATION OF SAID SOLENOID WITH ALTERNATING CURRENT; AND MEANS OPERABLE IN RESPONSE TO ACTUATION OF SAID ARMATURE TO MOVE SAID COMBINATION OF TIMING CAM AND CLUTCH SURFACE TO SAID ENGAGED POSITION. 